after a week with the new alternator everything was fine till today. I dont know if its the alternator but the tps value is fluctuating and causing the car to stall out just like when the alternators were dying.
what happens when the alternators start to die out is I will notice the car will have a hard time idling. sounds like its missfiring. I see the maft pro target airflow value jump around and will see on the scanmaster that the tps is moving from .5 to around .7 sometimes as high as 1. while I was limping it home today I noticed the volts on the scanmaster would occasionally drop to around 12.7. I drove around at a higher rpm to see if that charged up the battery and it somehow seemed to stabilize for a bit. Stopped at Advance Auto to test the charge system and everything came out ok. Although, I take that with a grain of salt because it tested ok before and then died the day after.
I'm still not ruling out the charge system but I went home and changed to a brand new ac delco tps. reset the IAC back to 21 at idle and set the tps back to .44. I will drive it around again once traffic settles down around here to see what that does.
I did some sleuthing and measured the diameters of the alternators I have. The Kirban alternator (still no word from them on a possible refund) measured about 65.5mm. The original alternator the car had when I bought it was 61mm. The impala alternator I have on now is 62.5mm (these numbers are approximate, any better way to measure diameter than calipers?). Interesting, three different diameters. I suppose if voltages continue to be the issue I will search for the appropriately sized pulley as well as maybe look into a new tensioner.